The inner core is indeed hotter than the outer core. However, the PRESSURE on the inner core is greater than the pressure on the outer core and the melting point of iron, the main constituent of the core, INCREASES as the pressure goes up. [ so because the pressure effect overrides the temperature effect, the inner core is solidified.
We also can speculate that the inner core began to freeze

(solidify) about 1 or two billion years ago. the inner core makes up only 1% of the mass of the Earth; the outer core makes up about 32% of the mass of the Earth. ]

Weegy: the alternating rise and fall in sea level with respect to the land, [ produced by the gravitational attraction of the moon and the sun. [ To a much smaller extent, tides also occur in large lakes, the atmosphere, and within the solid crust of the earth, acted upon by these same gravitational forces of the moon and sun. Tides are created because the Earth and the moon are attracted to each other, just like magnets are attracted to each other. The moon tries to pull at anything on the Earth to bring it closer. But, the Earth is able to hold onto everything except the water. Since the water is always moving, the Earth cannot hold onto it, and the moon is able to pull at it. Each day, there are two high tides and two low tides. ] (More)